Containers are commonly used to hold products such as milk, juices and other pourable products. It is desirable that the container be designed for repeated openings and closings so that any contents remaining in the container can be stored for use at a later time. Various prior art arrangements have been proposed in an attempt to meet that need.
For example, U.S. Pat. No. 4,782,996, discloses an openable and closable device that is attached to a container. The device includes a bottom member which is secured to the container and a cover that is hingedly connected to the bottom member. The bottom member includes a cutout portion that is aligned with a hole in the container when the device is attached to the container. A plug extending from the cover fits within the cutout portion in the base and the hole in the container. Protrusions extending from the outer peripheral edge of the plug engage the inner surface of the cutout portion in order to keep the cover in a closed position.
Similarly, in U.S. Pat. No. 2,676,744, an openable and closable closure device is attached to a container for permitting the removal of the container's contents. The device includes a bottom member having a cutout portion therein that is attached to the container so that the cutout portion is aligned with a hole in the container. A closure flap is hingedly connected to the bottom member. The closure flap has a flange which extends around the outer periphery thereof and a plug extending from a central portion thereof. In order to close the container after it has been opened, the closure flap is pushed downwardly so that the plug fits into the hole in the bottom member and extends into the interior of the container. Further, the closure flap is positioned relative to the container such that upon closure, the flange extending from the closure flap engages the outer peripheral edges of the container so that the closure flap remains closed.
Devices similar to those described above are also disclosed in U.S. Pat. Nos. 4,775,098, 2,927,695 and 2,321,050.
While the devices disclosed in the aforementioned patents permit a container to be opened and reclosed for use thereafter, those devices suffer from certain disadvantages. For example, some of those devices are designed so that the closure flap tightly engages the outer periphery of the container to which the device is attached in order that the closure flap will remain closed. Those devices must be positioned in close proximity to the peripheral edge of the container in order that flanges or the like extending from the closure flap can tightly engage the outer periphery of the container. Thus, those devices are not suitable for placement on all types of containers nor are they readily adapted to be placed anywhere on a container.
Also, if the top surface of the apertured bottom member through which the contents of the container are poured when the closure flap is open is substantially planar, it may be more difficult to pour the contents of the container through the aperture because there is no structure surrounding the aperture to control the flow of the contents, e.g. liquid, as it passes through the aperture. Thus, there is a tendency for the liquid to spill, drip and flow out of the container in an uncontrollable manner.
Another disadvantage is that the closure flap has a plug extending therefrom that fits through a cutout in the bottom member which is aligned with the hole in the container. Oftentimes, those devices rely upon the frictional engagement between the outer periphery of the plug and the inner wall of the cutout portion and/or the hole in the container in order to maintain the closure flap in the closed position. In the case of liquids, problem arises when the liquid in the container is poured through the cutout portion and the hole because residual liquid will adhere to the inner wall surface of the aperture and the cutout portion. Thus, when the closure flap is closed and the outer periphery of the plug engages the inner wall surface of the cutout portion and/or the aperture, the closure flap may actually become stuck in the closed position as a result of the sticky residual liquid on the inner wall surface. Further, the closure flap may not seal correctly.
Another problem is that the container to which the opening device is attached must be specifically adapted to receive the opening device. For example, the container may require a specific edge construction in order to securely hold the closure flap in the closed position or the container may require a laminated structure that will permit a portion of the opening device to be positioned between layers of the laminate. Such constructions limit the usefulness of the opening device because the opening device can only be used in conjunction with the specific container for which it was designed.
An additional drawback is that the opening device and the container are manufactured from the same material and are manufactured as an integral structure. Thus, the container must be specially manufactured to include the opening device. Further, such a construction offers no flexibility with respect to the positioning and orientation of the opening device.
When the product contained in the container is a product that is to be used or consumed by people, special concerns arise with respect to the possibility that the product may become contaminated or adulterated as a result of tampering. Notwithstanding the health and safety risks posed by such tampering, many of the prior art opening arrangements are not designed to permit a user to readily realize that the opening arrangement has been tampered with and that the contents in the container may not be fit for use or consumption.
Further, there is a concern that the opening arrangement may be inadvertently opened during handling and storage. Some prior art opening arrangements are not constructed to address this possibility and thus, are susceptible to undesirable spillage and emptying.
When adhesives are utilized to secure the opening arrangement to the container, it is desirable to control the placement of the adhesive and prevent it from flowing outwardly beyond the edges of the opening arrangement. In that way, the clean and attractive appearance of the container will not be diminished and the possibility that the adhesive will infiltrate the contents in the container will be avoided.
When the opening arrangement includes a stem that is to be inserted in a hole in the container, the position of the opening arrangement relative to the container must be maintained until the opening arrangement has been secured through suitable means to the container. Otherwise, a tight seal will not be obtained.